Which of the following is correctly stated as it happens in the common cockroach?

The cockroach has biting and chewing mouth parts; the mandibles crush the food, and the gizzard (proventriculus), which has six chitinous teeth, grinds the food particles further. This statement is correct.
Malpighian tubules (100–150 yellow filaments) arise at the junction of the midgut and hindgut, not from the colon.
The haemolymph has no respiratory pigment; oxygen reaches the tissues directly through the tracheal system.
The cockroach is uricotelic: its nitrogenous waste is uric acid, not urea.
Hence the correct statement is that the food is ground by mandibles and gizzard.